Adherence therapy for hypertension

Background: Poor adherence to drug regimens is a major cause of uncontrolled blood pressure (BP) in people with hypertension. Aim: To evaluate the efficacy of adherence therapy (AT) compared to treatment as usual (TAU) in reducing BP in non-adherent hypertensive patients. Additionally, a qualitative study was conducted to understand and explore patient's experience of AT. Design: A single blind parallel group RCT was conducted between August 2009 and January 2010, in outpatient clinics in Jordan. Patients were assessed at baseline and at 11 weeks by blinded assessors. At 11 weeks semi-structured qualitative interviews were also performed. Method: One hundred and thirty six adult patients with a mean baseline BP of 165 mm Hg (sd 10) over 102 mm Hg (sd 7) were randomly assigned to receive either TAU or AT which consisted of seven weekly 20 minutes sessions. The primary outcome was systolic blood pressure (SBP). Semi-structured interviews were conducted with 10 patients who had received AT. Results: AT lowered SBP by-23 mm Hg (95% CI: -26, -20) and diastolic BP (DBP) by -15 mm Hg (95% CI: -18, -13), improved adherence by 37%, and improved their beliefs towards taking medication at 11 weeks compared to TAU. The thematic analysis of the interview transcripts identified five major themes of patient's experience of AT; modifying attitudes and beliefs, positive impact on self efficacy, motivational therapist, positive impact on wellbeing, and a well designed intervention. Conclusions: Adherence therapy changes patients' negative beliefs and attitude toward antihypertensive drugs and this increases their adherence to medication regimes which then leads to a clinically important reduction in BP. This reduction could be predicted to lead to reduced incidence of the adverse consequence of hypertension such as strokes, myocardial infarction, or death